Food security is a major concern of the world in the context of increasing population, changing climate and declining scarce natural resources. Reducing food loss is equally important as increasing food production and productivity to feed the world, where 9.7 billion inhabitants were expected by 2050. Food loss can occur at several points along the food chain, however, harvest loss at the farm level is often overlooked which is directly impacting on sustainability. The paper attempts to estimate harvest loss at the farm level. A household survey was executed in 300 households from ten sample districts across Nepal. The percentage of harvest loss at the farm level was calculated for each crop grown as per -the season, plot and priority. Likewise, the multiple regression was executed to determine the level of influence of the socio-economic factors on the post-harvest loss at the farm level for the major crops. The mean harvest loss at the farm level found around 5 percent for the reported crops. The multiple regression model demonstrated that at the farm level, socio-economic factors might have a smaller influence on harvest loss as compared to physical and biological contributing factors. Nevertheless, reducing the post-harvest loss will increase food availability and thus the food security.